The present invention relates to a method for applying markings onto substrate surfaces using a transfer method in which a transfer layer on a prepared or pre-printed release carrier film is transferred immediately from the release carrier film onto the substrate surface, where it causes an adhesive image to appear that cannot be removed without destroying it.
The term “transfer method” is intended to refer to all printing methods in which a reversed or non-reversed transfer layer is applied to a release transfer film, and said transfer layer is transferred onto another substrate, where it causes an adhesive image to appear that cannot be removed without destroying it. Preferably, first a transferable pattern is created on the transfer film. In general, the pattern is only a printed image formed solely by the color coats. The carrier film is removed after the transfer process. Therefore, only the printed substrate surface is the carrier of the adhesive image.
The present invention is intended for use with all known transfer methods. The techniques described below are therefore to be understood as examples. The preamble of the main claim is intended to comprise all known transfer methods in which a transfer layer is transferred onto a substrate surface.
The detachment of the release carrier film can take place for example though detachment of a water-soluble adhesive bond between the release transfer film and the transfer layer; similar to a decal, a bond subsequently takes place between the substrate surface and the transfer layer. For the bonding, for example the rest of the glue remaining on the transfer image is used. The substrate surface can also be correspondingly set or prepared, for example with a thin coating of a bonding agent. Such a transfer method is called a wet transfer method.
Instead of a water-soluble glue, a thin permanent adhesive layer may also be used that can be detached from the release carrier film by mechanical separation. Such a transfer method is called a dry transfer method.
In addition, the hot transfer method is known, in which special printing inks are used that are applied onto the release carrier film as a transfer layer. Subsequently, the carrier film with the transfer layer is pressed onto the substrate with application of heat and pressure and the printing inks of the transfer layer detach from the carrier film. The above-named hot transfer method, also called the hot transfer printing method, is a method that is often used in textile finishing in order to transfer printed images (see the lexicon “Moderne Technik von A bis Z,” pub. TÜV Rheinland GmbH, Cologne, 1991; article. “Transfer printing”).
The transfer layer can be made up of a plurality of print layers applied in succession, and can for example also comprise a locally covering lamellar layer made of a printable material, for example dissolved natural rubber or PVC.
Preferably, a hot transfer method can also be used to mark substrate surfaces of washable and/or crumplable materials, such as textiles, films, or leather articles of clothing and the like. From a pre-printed release carrier film, a transfer layer on the release carrier film is transferred onto the material being printed by contact, under the action of heat, with the material, where it causes an adhesive image to appear that cannot be removed without destroying it.
In addition, using this and other transfer methods it is possible to transfer required colors in one pass. The print inks are transferred onto the surface of the material under the action of heat, and cannot be removed from the material without destroying the printed image. The printed image serves, for example using marks or signs, to label the respective material or products produced therefrom.
The products can be crumplable and washable, and correspondingly the inks used can also have these properties.
In particular on film-type substrates, transfer layers can also be transferred using the wet transfer method. The resulting image on the substrate is relatively brittle and cannot be removed without destroying it.